Indians sip only two liters of beer a year, just one-twentieth the amount consumed by Chinese and less than one-fortieth by Americans. SABMiller Plc (SAB), Anheuser- Busch InBev NV (ABI) and Carlsberg A/S (CARLB) see that as an opportunity.

The global brewers are forming partnerships, introducing new products and marketing milder, pricier brews to young Indians. They have yet to overcome a maze of regulations and United Breweries Ltd. (UBBL), owner of top local brand Kingfisher, in a market expected by Euromonitor International to almost double to $9 billion by 2016.

United Breweries so far has beaten back the challenges. It started selling Heineken in India over the past seven months to offer more options against foreign rivals. Changing state regulations have already eaten into London-based SABMiller’s market share and all of the brewers still face some Indian taboos on alcohol consumption.

“Everyone fantasizes: Imagine if you had a billion Indian people drinking 50 liters of beer per capita,” said Trevor Stirling, analyst at Sanford C. Bernstein Ltd. in London. “It’s going to be many decades, if ever, before Indian per capita consumption reaches 50 liters.”

Emerging markets such as India are important to global brewers as growth slows in the developed world and brands like Budweiser fight competition from craft beers in the U.S.

At the same time, the experiences of foreign brewers show how regulations or entrenched competitors are holding back many of the world’s largest companies in the second most populous nation. Retailers such as Wal-Mart Stores Inc. (WMT) faced a setback in December when the government reversed a decision to allow their entry into a market dominated by local mom-and-pop stores.

India also bans advertising of alcoholic drinks, which can make it harder for brewers to introduce consumers to new names.

Supplying British Troops United Breweries traces its roots to British soldiers’ love for beer. In 1915, a Scotsman named Thomas Leishman bought five breweries in southern India to form United Breweries. The company transported its beer in barrels on bullock carts, serving British troops. Vittal Mallya, father of present chairman Vijay Mallya, bought United Breweries in 1947, and snapped up distillers and brewers on the cheap when the Indian government briefly threatened prohibition in the 1970s.

The sale and distribution of alcohol in India is controlled by state governments, which impose taxes on imports and exports, forcing companies to open distilleries and breweries in each state where they want to sell their products cost-effectively.

“The biggest challenge is, in India, every state has their own system in terms of taxation, labor requirement,” said Joergen Buhl Rasmussen, chief executive officer of Copenhagen- based Carlsberg, which entered the country in 2007. “That does make India not very efficient to operate.”

United Breweries benefits from 28 breweries spread across the country’s 28 states. That tops the 13 that SABMiller uses and Carlsberg’s five.

New Beers United Breweries, based in Bangalore, increased its beer market share to 57 percent in 2011 from 43 percent in 2006, according to London-based Euromonitor. In the same period, SABMiller’s share dropped to 24 percent from 37 percent.

The success of the brewing business contrasts with United Breweries parent UB Group’s money-losing Kingfisher Airlines Ltd. (KAIR) The airline, which has reported more than 10 straight quarterly losses, is seeking new funds after grounding planes and cutting flights because of a cash shortage.

Kingfisher has held its own in the beer market helped by the introduction of new products, including milder, higher- priced varieties like Kingfisher Ultra.

“When we were going to launch Kingfisher Ultra two years ago, we used to wonder who would buy a 100-rupee ($2) beer,” Samar Singh Sheikhawat, vice president of marketing at United Breweries, said in an interview in August when the company introduced Heineken in India. “But today, Kingfisher or the mainstream beers are close to 90 or 95 rupees. What was considered a barrier for beer doesn’t exist anymore.” Regulatory Disputes SABMiller also added brands, such as Miller High Life, to reach young, urban consumers. Its market share was still hurt by regulatory disputes in the states of Andhra Pradesh and Uttar Pradesh, and excise duty increases in other states, the company said in its 2010 annual report.

“The single greatest challenge that any brewer faces is regulation,” Derek Hugh Jones, marketing director of SABMiller India, said in an e-mail. “The movement of beer across state borders is inefficient, eliminating any scale efficiency.”

Still, consumers’ greater affluence and increasing social acceptance of beer will “ensure sustained growth” for the industry in India, he said.

Religious Taboos Per capita consumption of beer in India at 1.6 liters is a fraction of 35.5 in China, 75.6 in the U.S. and 105.6 in Germany, based on Euromonitor estimates.

“You have a reasonably high proportion of a Muslim population who won’t drink alcohol,” said Stirling. “Also, if you’re a devout Hindu, you won’t drink alcohol.”

Social norms are changing and beer consumption picking up as India’s young adults have more money to spend and travel around the world. The economy has grown at an average annual pace of more than 8 percent for the last four years. Euromonitor estimates India’s beer market will grow to 447.9 billion rupees ($9 billion) from 257 billion rupees in 2011.

Carlsberg’s Rasmussen said the potential to raise per capita purchases makes the country “a very attractive market to be in over time.”

Carlsberg, which entered India in 2007, had a 4.4 percent share in 2011. Anheuser-Busch InBev, the Leuven, Belgium-based company that sells its Budweiser beer, held 1.1 percent.

Stronger Tastes One factor in the new brew battles: the strength of the beer. Indian drinkers are largely still partial to stronger beers like Kingfisher Strong, with an alcohol content that can go as high as 8 percent.

As much as 80 percent of the beer sold in India’s beer industry is “strong,” with alcohol content of six to eight percent, by Sheikhawat’s estimate.

United Breweries’ stable of brands includes Kingfisher Strong and Draught as well as milder variants such as Ultra. Carlsberg has introduced stronger brews, including Carlsberg Elephant and Tuborg Strong.

Microbreweries are springing up in India as well. The New Delhi suburb of Gurgaon has several. One of the largest, called Rockman’s Beer Island, has raised prices as many as four times since starting in 2009 and still has customers flying to its brewery, on the top floor of an upscale mall, from other cities.